The present invention relates to an apparatus for elevational adjustment of a traveling service unit vertically with respect to an associated textile machine in a textile spinning mill and, more particularly, to an apparatus of the aforementioned type for vertically adjusting a traveling service unit with respect to a longitudinal guide rail along the spinning mill machine on which the service unit is guided by at least one guide element.
Traveling service units of the aforementioned type are commonly operated in association with various machines in textile spinning mills for performing automatic servicing functions thereon, such as the doffing and donning of bobbins and the piecing of broken yarn ends. In order for such service units to function reliably, the units must be precisely adjusted in elevation with respect to the associated spinning mill machine.
In this regard, it has been suggested in the prior art that elevational adjustment of traveling service units with respect to the associated textile machine may be achieved by guiding the service unit along a supporting rail which is mounted to the associated machine in precise relative adjustment thereto. However, in this arrangement, the entire weight of the traveling service unit, which often is considerable, must be supported by the machine. For this reason, the framework of such textile machines must be suitably reinforced, but nevertheless the machine framework undergoes detrimental deformation during traveling movement of the service unit.
It has also been suggested in the prior art to provide the traveling service unit with floor-supporting rollers to transfer at least a portion of the weight of the service unit to the supporting floor with only the remaining portion of the weight of the service unit being required to be supported by the guide rail of the spinning mill machine. Hereagain, however, the frame of the spinning mill machine is still required to support a considerable portion of the weight of the traveling service unit.